INDIANAPOLIS – The Indiana Pacers are doing it again Friday night in Game 3, having another one of those anemic quarters they’ve had in each playoff game with the Boston Celtics, and Thaddeus Young can’t take it anymore. He has just missed two shots at point-blank range, two of the five shots the Pacers missed on this empty possession in the third quarter of this 104-96 loss, and he’s walking away from his teammates during a break in the action, into a corner, where he starts smacking himself in the face: Left, right, left …

This is what it feels like for the Pacers, who keep losing winnable games to the Boston Celtics, and did it again Friday night to fall into a 3-0 hole that nobody in NBA or ABA playoff history has escaped. They are beating themselves, and because of that, they are beating themselves up. When this 2019 NBA playoff series ends – and it will end soon, perhaps Sunday in Game 4 – they will have nobody to blame but themselves.

Indiana Pacers guard Tyreke Evans (12) drove between Boston Celtics forward Marcus Morris (13) and Terry Rozier (12) in the second half of their game at Bankers Life Fieldhouse on Friday.(Photo: Matt Kryger/IndyStar)

“Very frustrating,” Young was saying in the quiet mausoleum of the Pacers’ locker room.

Across the room, Darren Collison and Bojan Bogdanovic are locked into an angry conversation. Not mad at each other, but at the game, the result, the series. Bogey is waving his arms dismissively, disgustedly. Collison is nodding. He is seething. I leave Young, who is berating the Pacers’ offensive execution, to ask Collison why he’s so angry.

“Every game is right there,” he says.

They are. This one was. The names on the court – Kyrie Irving, Jayson Tatum, Gordon Hayward, Jaylen Brown, Al Horford … – say the Boston Celtics have a decided edge in talent. And probably, they do. OK: Definitely, they do. And yet, these games have been so winnable. Which means, for the Pacers, this series is so painful.

Every game is right there.

When this is over, the Pacers are going to spend the offseason making like Thaddeus Young and beating themselves up. Their starting five, in particular, will be miserable. Because their starting five is playing miserably:

Just one starter, Darren Collison, is shooting 40 percent or better on the series – he’s at 43.8 percent – and none of the five is scoring at his season average. And let’s expand that fivesome by one and include Sixth Man of the Year candidate Domantas Sabonis, who has disappeared against the Celtics. After setting a franchise record by shooting 59 percent from the floor this season – averaging 14.1 points and 9.3 rebounds – Sabonis is shooting 30 percent in three games against the Celtics (6-for-20) and averaging 6 ppg and 6 rpg.

And it’s not just Sabonis. It’s everybody failing for the Pacers. Bogdanovic was 6-for-17 on Friday night with a killer turnover late, getting his pocket picked by Kyrie Irving in a two-point game. Irving went the other way, scored to make it 93-89 with 4:17 left, and it was never a one-possession game again.

But again: It was everyone in the Pacers’ starting five, which was a combined 23-for-57 from the floor (40.3 percent).

And when the Celtics succeed? Here’s what Collison was telling me after Game 3: It’s everybody for the Celtics succeeding.

“You watch how they’re playing,” Collison was saying. “It all comes down to execution. They’re using each other, they’re running their sets. Different guys are having their moment within the offense. When they run their play set, the plays aren’t for any one individual. It’s for the whole team. That’s something we can take away for ourselves.”

The Pacers, meanwhile, are bogging down on offense. They call a play, and if it doesn’t work early in the shot clock, heaven help whoever has the ball.

“We have to make the extra pass,” Young said, “or we have to get another guy into a screen and roll. Those extra ball-movement plays are the ones that kill us, because we get ourselves into the shot clock and we start going one-on-one with jump shots.”

On Friday night, the Pacers had just one guy who could make a jump shot. It was Tyreke Evans, of all people, and with 5½ minutes to play and the Celtics leading 91-87, he came out of the game. By the time Evans returned, the Celtics led 102-94, there were 47.9 seconds to play, and thousands of Indiana fans wearing “Gold Don’t Quit” T-shirts were doing just that and heading for the exits.

For the season, Evans has largely been a disappointment (10 ppg on 38.4-percent shooting, 2.9 rpg, 2.4 assists), but let’s be fair and describe what he was on Friday night: The best player the Pacers had. He scored 19 points in just 22 minutes – fewer minutes than starting guards Collison (10 points in 26 minutes) and Wesley Matthews (11 points in 32 minutes), and fewer than reserve guard Cory Joseph (five points in 23 minutes).

But Evans was the one keeping the Pacers in the game, playing the way he plays – with no discernable conscious – and seeing it work because he was making his shots.

Hitting eight of their first 10 attempts from 3-point range, the Celtics blew to a 41-28 lead after one quarter, but the Evans-led second unit brought the Pacers back. Evans drove the lane for a twisting layup. He hit a 3-pointer. Attacked Marcus Morris in transition and scored in his face. When Evans hit a 3-pointer on Hayward with 5:01 left in the first half, the score was tied at 52. Evans scored 15 points in his 11 first-half minutes, leaving the court to a standing ovation late in the half.

But the second half happened, and the Pacers disappeared again for an entire quarter. In Game 1 they scored a franchise playoff record-low eight points in the third quarter of an 84-74 loss in Boston. In Game 2, for the first time in franchise postseason history, they played an entire quarter without scoring a two-point field goal; that was the fourth quarter, when Boston outscored the Pacers 31-12 to turn a 79-68 deficit into a 99-91 victory.

In Game 3, it was the third quarter. The Pacers scored just 12 points and had to get hot to do that, having scored just three points in the first six minutes. By the time the period was over, the Celtics led 80-73 and never trailed again.

“We all know what it is for us,” Young said. “It’s just that one quarter that’s killing us. We worked ourselves back in position of the game, and the third quarter just killed us.”

Their season is on life support. NBA and ABA teams facing a 3-0 deficit in a best-of-seven series are 0-146. A comeback from 3-0 has never happened. It probably won’t happen now.

But these games. They’ve been so close.

The Celtics keep finding a way to win. And the Pacers, well, they keep finding a way to lose.